Purposes/Aims: This study explored expanded sociodemographic and mental model constructs from the TERA Model as predictors of indoor radon risk reduction behavior among rural, low-income Montana families (n=170). Rationale: Rural conceptualizations of environmental justice are important in narrowing the gap in health disparities yet little is known about precautionary behaviors related to environmental health exposures for young, rural families with children. Method: Survey data were collected from recipients of public health services who earned less than 200% of the federal poverty level (n=170) and lived in radon Zone 1 designated counties. Logistic regression analyses tested the utility of a theoretically supported model in predicting radon risk reduction behaviors. Results: From questionnaire data, ninety percent of study participants had not tested their homes for radon. Radon risk reduction behaviors did not differ by householder status (rent/own) (c2 (1, 170) =1.32, p=.25; OR=1.06; CI=0.95-1.2; p=.3 Fisher's Exact Test). A model of five sociodemographic and three mental model variables were significant in predicting whether participants who had not tested their homes had ever heard of the health effects of radon (c2 (8, 153) =21.07, p<.01). Years of education and radon knowledge score were variables retained in the final model (c2 (2, 153) = 21.32, p<.01, Nagelkerke R2=0.17). Implications: Public health providers in high radon areas should not assume that low-income families understand radon-related risks. On the contrary, half of the participants in this study were unaware of the health effects of radon, despite ongoing public awareness efforts by local health, housing, and weatherization agencies. Educational programs targeted for salient sub-populations are needed if the public is to be protected. Conceptualizations of environmental justice in rural Western communities should consider the roles of income, education, and social class in regard to risk characterization.